Astronomy is the study of the origin, evolution, distribution, and future of life in the universe. This interdisciplinary field encompasses the search for habitable environments in our Solar System and habitable planets outside our Solar System, the search for evidence of prebiotic chemistry, laboratory and field research into the origins and early evolution of life on Earth, and studies of the potential for life to adapt to challenges on Earth and in outer space. Astronomy addresses the question of whether life exists beyond Earth, and how humans can detect it if it does. (The term exobiology is similar but more specific it covers the search for life beyond Earth, and the effects of extraterrestrial environments on living things)
Astronomy makes use of physics, chemistry, astronomy, biology, molecular biology, ecology, planetary science, geography, and geology to investigate the possibility of life on other worlds and help recognize biospheres that might be different from the biosphere on Earth. Astronomy concerns itself with interpretation of existing scientific data; given more detailed and reliable data from other parts of the universe, the roots of Astronomy itselfphysics, chemistry and biologymay have their theoretical bases challenged. Although speculation is entertained to give context, Astronomy concerns itself primarily with hypotheses that fit firmly into existing scientific theories.
Earth is the only place in the universe known to harbor life, therefore, astrobiologists must base their work on only one example: Earth. However, recent advances in planetary science have changed fundamental assumptions about the possibility of life in the universe, raising the estimates of habitable zones around other stars and the search for extraterrestrial microbial life.